All computers on the Internet use a TCP/IP protocol for communication. An IP address or a name, or both, identify the web sites/computers connected to the Internet—both servers and clients. For example, the Ragula Systems web site can be identified by its domain name www.fatpipeinc.com or by its IP address 206.71.77.143 (FATPIPE is a mark of Ragula Systems, which does business as FatPipe Networks). Computers on virtual private networks, on other wide area networks, on intranets, and on other networks also use TCP/IP. As a general rule the name of the web site on any of these networks tends to remain constant while the IP address associated with it can change based on the IP address(es) of the server(s) on which the site is hosted.
Communication between the computers uses TCP/IP protocol to access the web site data. Therefore, it is necessary to convert the domain name of the web site to the IP address of a server of the web site. Domain Name Service (DNS) servers connected to the web/Internet perform the conversion of name to IP address using a DNS protocol; this conversion is call “domain name resolution”. A domain name resolution request is a request for an IP address that corresponds to a given domain name; more than one IP address may correspond to a given domain name if the web site named is heavily used. An Internet Service Provider (ISP) may provide the IP address of a DNS server to its customers. This DNS IP address is input in the configuration of the TCP/IP stack on the computer connecting to the Internet and may be input to a Dynamic Host Configuration Protocol (DHCP) server so that it can provide TCP/IP auto-configuring information to other computers. Requests from customers for access to a web site are directed to the DNS server, which resolves the domain name in the request to obtain a corresponding IP address that can be used by routers to forward the web site access request to a server for the web site.
U.S. Pat. No. 6,154,777 discusses a context-dependent name resolution system. In one example, a domain name is bound to a list of IP addresses, and policies involving requester information, destination information, or request content are used to bind a particular IP address to the domain name in response to a particular request. Examples of resolution based on requester information comprise resolution based on the domain name of the sender, the actual geographic region of the sender, the quality of service desired by the requester, or the requester's time of day or time zone. Examples of resolution based on destination information comprise resolution based on the load at the receiving server, or the actual geographic region of the receiver. Examples of resolution based on request content comprise selecting an IP address based on the type of service requested or the specific information requested. This patent also states that resolution may be based on random selection of the destination from a qualified list, and other independently developed information.
In particular, the '777 patent discusses domain name resolution based on destination server loads. But there is apparently no discussion of basing domain name resolution results on the load or availability of routers or connections to destination servers, as opposed to using the status of the servers themselves. U.S. Pat. No. 6,205,489 similarly focuses on web servers rather than the routers and other connection components in paths to the servers. The same holds true of other previous efforts.
Accordingly, it would be an advancement to provide domain name resolution tools and techniques that provide IP addresses based on criteria such as router loads and connection availability. Such tools and techniques are discussed and claimed below.